Field of the Invention
The present invention relates to an insertion device, an image forming system including the insertion device, an image forming device including an insertion function, a method executed by the image forming device, and a control program to control the image forming device.
Description of the Related Art
By connecting a post-processing device to an image forming device, it becomes possible to perform various kinds of post-processing such as folding, punching, binding, cutting, and insertion with respect to a recording medium on which an image is formed.
For example, in insertion processing, a recording medium such as cardboard or colored paper (hereinafter, also referred to as second recording medium) is inserted into a flow of conveyance of a plurality of recording media on which images are formed (hereinafter, also referred to as first recording medium).
As such a technology, in JP 2014-5138 A, a conveyance system including a conveyance device to form an image on a first recording medium and an insertion device to insert a second recording medium between a plurality of first recording media on which images are formed is disclosed.
In the conveyance system of JP 2014-5138 A, the insertion device calculates insertion preparation time based on time necessary until the second recording medium housed in the insertion device is converged to a conveyance path where the first recording medium is conveyed. Then, in consideration of timing at which insertion of the second recording medium is completed, the conveyance device determines, based on the insertion preparation time, paper-feed timing of the first recording medium which feeding follows the insertion of the second recording medium.
Thus, according to the conveyance system of JP 2014-5138 A, the first recording medium which follows the second recording medium does not collide with the second recording medium. Moreover, according to the conveyance system of JP 2014-5138 A, the first recording medium can be fed before insertion of the second recording medium is completed as long as collision with the second recording medium is not caused at the timing. Accordingly, productivity can be improved.
However, in the above conveyance system, the conveyance device determines paper-feed timing of a following first recording medium based on the insertion preparation time calculated before the second recording medium is conveyed. Since the insertion preparation time is previously calculated, it is necessary to calculate the insertion preparation time in consideration of the longest time (hereinafter, also referred to as maximum time) on the assumption of various cases. For example, when conveyance of the second recording medium is started in the insertion device, first, it is necessary to separate one second recording medium from a tray in which a plurality of second recording media is housed. Thus, due to a variation in the number of second recording media loaded in the tray or a degree of abrasion of a separation mechanism such as a separating roller to separate a second recording medium from the tray, separation time of the second recording medium varies. Thus, in the conveyance system, it is necessary to calculate the insertion preparation time according to the maximum value of the separation time.
In such a manner, when the insertion preparation time is calculated in consideration of the maximum time, paper-feed timing of a following first recording medium is delayed due to the maximum value of the separation time even in a case where actual separation does not take much time. Thus, productivity is decreased. The present invention has been made to solve the above problem.